1. Field of the Invention
The invention relates to a laser detection apparatus having the features of the precharacterizing clause of the attached claim 1, and to a laser detection method which can be carried out using said apparatus, having the steps of the precharacterizing clause of the attached claim 10. A laser detection apparatus such as this and a laser detection method such as this are known from DE 198 51 010 A1.
2. Background Information
In particular, the invention is intended to solve the problem of fast and robust identification and location of laser beam sources—in particular laser threats—by means of a laser warning system. Laser threats are caused, for example, by laser range-finders, laser target designators, laser beam riders or snipers.
The following description refers to the following references or documents and also relates to the ALTAS products from EADS Deutschland GmbH:    [1] “Einrichtung zur Erkennung und Lokalisierung von Laserstrahlungsquellen” (Kreuzgitter), [Device for identification and location of laser radiation sources” (cross grid)], filed Nov. 5, 1998, laid-open: Jun. 14, 2007, DE 198 51 010 A1,    [2] “Verfahren und Vorrichtung zur Erkennung, Lokalisierung und Verfolgen von Laserstrahlungsquellen” (Zeilen-Gitter) [“Method and apparatus for identification, location and tracking of laser radiation sources” (line grid)], German patent application from EADS Deutschland GmbH dated Jan. 29, 2007, inventor: Herr Thorsteinn Halldorsson;    [3] Gonzales and Woods, Digital Image Processing, Pearson Prentice Hall, 2008 (oder andere Lehrbücher der Bildverarbeitung) (or other image processing textbooks).
In particular, the ALIAS product range from EADS Deutschland GmbH and [1,2] can be cited as prior art.
In particular, DE 198 51 010 A1 discloses a laser detection apparatus and a laser detection method in which an interference pattern is produced from detected light and the interference pattern is investigated to determine whether it exhibits typical laser interference. An image processing unit is provided for this purpose, the aim of which, in particular, is to detect the symmetry of light spots, the position of a symmetrical light spot structure, and the intervals between the light spots.
The aim of the analysis of the interference pattern in the image processing unit is, in particular, detection of a grid interval and the position of the grid structure of laser interference points. However, the prior art does not describe how this analysis can be carried out robustly and quickly.